Version: Update for TF-M v1.2.0 release

This patch updates the TF-M version for runtime code,
build system and documentation to v1.2.0

Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
Change-Id: I53b1e916a9928bac7347381d1a37c7d62bd2302a
diff --git a/secure_fw/spm/include/tfm_version.h b/secure_fw/spm/include/tfm_version.h
index 25354e9..82e1e0e 100644
--- a/secure_fw/spm/include/tfm_version.h
+++ b/secure_fw/spm/include/tfm_version.h
@@ -12,7 +12,7 @@
  * Defines for TFM version.
  */
 #define VERSION_MAJOR    1
-#define VERSION_MINOR    1
+#define VERSION_MINOR    2
 #define VERSION_HOTFIX   0
 #define VERSION_STRING   ""